Buildings such as factories, office buildings, and homes typically require the transport of air to, within and from such buildings. This may involve the removal of stale air, as well as the distribution of air conditioned in a variety of ways, including heating, cooling, adding or removing moisture and filtration, to name some examples. The technology and systems related to the conditioning and distribution of air in buildings are generally referred to by the acronym HVAC (Heating, Ventilating, and Air Conditioning).
In some HVAC systems, ducts may be used to remove air or distribute conditioned air throughout a building. The ducts used in a HVAC system are often collectively referred to in the art as “ductwork”, and individually as “ducting”. Some HVAC systems may also incorporate the use of fans or other mechanisms to force the air through the ductwork, as well as components to condition the air, such as furnaces or humidifiers.
One common type of ducting is a rectangular duct formed from sheet metal, commonly referred to in the art as “rectangular metal duct”. This type of duct is formed by constructing separate, hollow, and elongated sections of duct, and connecting same together so as to form ductwork through which air may be transported.
As air must typically be transported throughout a building, ductwork is also typically installed throughout a building, preferably in unobtrusive locations. Therefore, one common installation procedure is to suspend ducting from elevated supports, such as overhead pipes or the surfaces of ceilings.
There are a number of ways known in the art to suspend rectangular metal ducts from a support. Most commonly, one end of a length of steel wire, steel strap or threaded rod may be anchored to a support using any of a variety of mechanisms well known in the art. The other end of the length of steel wire, steel strap or threaded rod may then be connected to the duct to provide support for the duct. Steel wire and steel straps may directly support the duct by encircling the duct, whereas threaded rods are generally used in conjunction with a cradle bar, also known in some circumstances as a support channel, that supports the duct from below. Cradle bars are widely used to suspend rectangular metal ducts, and generally involve supporting a duct from below at regular intervals with a cradle bar, with each terminal end of each cradle bar being connected to one end of a threaded rod, with the other end of the threaded rod being anchored to supports such as an overhead pipe or ceiling surface. Although steel wire may be employed to directly support a duct as aforesaid, steel wire may also be used in conjunction with cradle bars if so desired.
Unfortunately, there are problems associated with prior art methods of supporting rectangular metal duct. These include high labour and material costs and the structural integrity of the support methods. For instance, it has been known with steel wire that the latter can at times cut into the sheet metal wall of a duct which it directly supports, depending on weight considerations. With regard to cradle bars, lengths of cradle bars must typically be cut to size to correspond to the width of the particular ductwork being supported, thereby increasing the labour costs of their manufacture or installation. Also with regard to cradle bars, the lengths of supporting steel wire or rod which must be deployed in installation must be long enough to reach the bottom supported surface of the affected ductwork, given that the cradle bars are typically located and support the ductwork from underneath same. Accordingly, there is a need for a method, and apparatus, for connecting a duct to a support, which is intended to assist with eliminating or alleviating some or all of the aforementioned problems associated with the prior art approaches.